GVI is the file extension for Google Video File, this is a video format that was developed by Google and was used as their proprietary video format. It got discontinued in 2007. The original idea was supposed to solve compatibility issues, Google Video Player was another way to view Google videos and importantly it was able to run smoothly on both Windows and Mac OS X.
The GVI format is similar to an .AVI file; it is encoded in DivX4 with an MP3 compressed audio track. They are similar to .avi files but have an extra list containing the FourCC goog immediately following the header. The list can be removed with a hex editor to avoid playback issues with various video players. The video is encoded in MPEG-4 ASP alongside an MP3 audio stream.
Google VideoPlayer VideoLAN VLC Media Player Windows MediaPlayer classic